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Prediction of Aggregate Packing with Tubular Macrocapsules in the Inert Structure of Self-Healing Concrete Based on
Harry Hermawan1,2, Alicia Simons1, Silke Teirlynck1
1Department of Civil Engineering, Materials and Constructions, Ghent Campus, KU Leuven, Gebroeders De Smetstraat 1, 9000 Ghent, Belgium.
Materials (Basel, Switzerland)
|May 25, 2024
Summary
This study investigates tubular macrocapsules in concrete packing systems. Findings show macrocapsules increase voids ratio in coarse aggregates, necessitating model adjustments for accurate predictions in self-healing concrete design.
Area of Science:
- Materials Science
- Civil Engineering
- Concrete Technology
Background:
- Designing inert structures for self-healing concrete requires understanding particle packing.
- The influence of inclusions like macrocapsules on aggregate packing is not fully understood.
Purpose of the Study:
- To investigate the effect of tubular macrocapsules on aggregate packing systems.
- To evaluate existing particle packing models and propose an improved model incorporating macrocapsules.
Main Methods:
- Experimental evaluation of voids ratios (U) in aggregate mixtures with varying macrocapsule types, sizes, and dosages.
- Comparison of experimental results with Dewar's particle packing model.
- Analysis of macrocapsule effects on coarse and fine aggregate packing.
Main Results:
- Macrocapsules significantly affected the packing of coarse aggregates but not fine aggregates.
- Increased capsule dosage and aspect ratio led to higher voids ratios.
- Dewar's model required modification to accurately predict packing with macrocapsules.
Conclusions:
- A new 'U model' for macrocapsules was proposed, offering high prediction accuracy for voids ratio.
- Findings provide insights for optimizing the design of self-healing concrete inert structures.
- Minimizing packing disturbance involves increasing fine aggregate content over coarse aggregates.
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